Mandrel for battery jars



June 22 1926.

J. H. wAGENHoRsT MANDREL FOR BATTERY JARS Filed Feb. 24, 1919 Patented June 22, 1926.

UNITED STATES JAMES H. y'lTAC-Ifile".'.N'HORS'II, OF AKRON, yOHIO.

MANDREL FOR BATTERY JARS.

Application sled February 24, 1919. serial No. 278,639.

This invention relates generally to manf drels for making hard rubber jars for storage batteries.

lHeretofore mandrels or forms have been made of cast iron, and the forming surface thereof was machined and polished in order to provide a smooth surface, and consequentvly a mandrel or form made in this manner was very expensive.

Furthermore a cast iron mandrel or form was subject -to attack from the lvarious ingredients of the rubber compound, and constant care was required in order to keep vthe surfaces perfectly smooth and prevent scaling or tearing o' of a portion of the molded article when the mandrel or form was withdrawn.

The object of myinvention, therefore, is to avoid this defect and provide a mandrel or form which can be quickly and easily manufactured, one which does not require any machining, and one-which will not deteriorate under use; and with this object in view -my invention consists in providing a mandrel or form of lead having arranged therein a core or base of cast iron, or other suitable rigid material, capab-le of with? standing the pressure placed upon said man' drel or form while the material is being moulded upon the exterior thereof.

The invention consists also in certain details hereinafter fully described and pointed l out in the claim.

In the drawingslforming a part of this lspecification Fig. 1 is a perspective view of a mandrel constructed in accordance with' my invention, one corner of said mandrel being shown in section in order to disclosethe two thicknesses of different metals; and Fig. 2 is a vertical sectional view of a mandrel' or form constructed in accordance with my invention..

Referring to the drawings A indicates the .core or base which is preferably of cast iron,l

and its exterior is made of the contour or shape of the ultimate mandrel but slightly smaller than the finished article, arid if desired this core or base can be formed with one or more reenforcing partitions as most clearly shown inFig. 2. The coreis also lprovided with an outwardly extending base ange A2 which serves to keep the mandrels spaced apart in the vulcanizer yso that the f rubber articles bein vulcanized will not contact with one anot er andV this base flange also provides means for holding the mandrel while the vulcanized article is being stripped therefrom.

Covering the exterior of this cast iron coro or base is an envelope or skin B of lead, this outer covering envelope or skin being placed completely over and made to completely cover the cast iron base or core as most c1early shown.

Thus it will be noted that the cast iron base is made with transverse indentations A and the lead covering is pressed into'the.

same as most clearly shown at B", this form beingmade in this manner in order to produce the transverse ridges or ribs in the bottom ofthe jar, but it will be understood that the same method of manufacture is followed in connection with various types of mandrels, that is, the cast metalA base or core has the general shape and contour of the@ mandrel and the ultimate finished shape and dimension is provided by the lead covering or skin which completely envelops the cast :metal base or core.

The lead covering takes a perfectly smooth slippery finish and the mandrel as a whole j can be quickly and easily withdrawn from the molded article without any danger whatever of scaling or stripping the inner edges thereof, and the lead covering is not injuriously affected in the least by the chemical ingredients of the rubber compound and ifl anything is improved.

It will be understood, that in operation, a

blank sheet of rubber is folded by proper mechanical appliances about the mandrel, and pressure applied thereto in order to properly shape the article7 in this instance the battery jar.

i An entire `mandrel of lead would not have `suiiicient rigidity to withstand the pressures placed thereon and consequently a-core of cast metal is needed to withstand these pressures, but having a rigid back of cast metal, the thin coating or covering of lead will not be indented or injured in the least by such pressure. j

Consequently a thoroughly practical and eificientmandrel can be provided at a com- Having thus described my invention, what.

5 I Claim isv:

A mandrel for forming rubber battery surface unaffected'V by .the chemicals. of the rubber compound, said envelope covering the 10 side and top walls of said core and extending down to and terminating at said `base flange.

In testimony whereof, I hereunto aix my C' signature.

jars comprisin an iron core having a base 4flange and a eaden envelope providing a 'JAMES H. WAGENnoRsT. 

